1. Field of the Invention
The present invention relates to patterned media. Moreover, the present invention relates to a method of manufacturing a magnetic recording medium, and more particularly to a magnetic recording medium used for information recording media. Further, the present invention relates to a method of manufacturing a base.
2. Description of the Related Art
With recent rapid increase in information processing quantity, realization of large increase in capacity is required in magnetic recording media widely used as an information recording medium. Particularly, in hard discs, large increase in capacity and large increase in recording density have been realized until now with development of fine processing technology and signal processing technology, etc. being supported. However, nowadays, recording density is becoming close to about 200 Gbits/in2 which has been considered to be physical limit from the problem of thermal fluctuation in the conventional in-plane recording system in which magnetization is recorded in a substrate in-plane direction, and increasing speed of the recording density becomes gentle. In recent years, hard discs of the system of recording magnetization in a substrate perpendicular direction which is the so-called perpendicular recording system, which has been considered to be tolerable to the problem of the thermal fluctuation have been realized as products. From this fact, it is expected that further improvement in the recording density will be realized also in future.
However, for realization of higher density in future, increase in noise becomes a large problem. Namely, there is the problem that unevenness of shape and size of magnetic particle constitutes cause of noise followed by reduction of recording bit based on realization of high recording density to deteriorate recording/reproducing characteristic. To solve this problem, it is considered that reduction in exchange interaction between adjacent magnetic particles, and miniaturization of size and realization of uniformness of shape of magnetic particle are effective.
Particularly, a medium in which control is performed to the extent of arrangement of magnetic particles by making use of fine processing technology so that magnetic particles which are uniform in shape and size are regularly arranged is called a patterned medium. Thus, attention is drawn to the fact that ultra-high density medium having the recording density of the order of 1T bits/in2 can be realized.
To prepare such a patterned medium, there is mentioned a method of implementing processing such as etching, etc. to magnetic layer to prepare regularly arranged magnetic particles which are uniform in shape and size (Japanese Patent Application Laid Open No. H9-297918).
However, there are instances where the magnetic layer is etched so that the magnetic layer may be damaged.